Running Python on Your Computer

To start coding in Python, you need to have Python installed on your computer. Follow the installation guide on our Installation Page if you haven’t done so already.

Once Python is installed, you can run Python code using the command line or terminal.

Using the Command Line or Terminal

1. Open the Command Line (Windows) or Terminal (macOS/Linux):

   • Windows: Press Win + RWin + R, type cmdcmd, and press Enter.
   • macOS/Linux: Use the terminal application.

2. Navigate to Your Python File’s Directory: Use the cdcd command to navigate to the directory where your Python file is located. For example:

   command

   cd path/to/your/python/files

   command

   cd path/to/your/python/files

3. Run Your Python Script: Execute your Python script using the pythonpython command followed by the filename with the .py.py extension.

   command

   python your_script.py

   command

   python your_script.py

Creating Your First Python File

1. Open a Text Editor: Use a text editor (e.g., Visual Studio Code, Sublime Text, or Notepad) to write your Python code.

2. Write Your Python Code: Create a simple Python script, for example, a “Hello, World!” program:

   main.py

   # hello_world.py
   print("Hello, World!")

   main.py

   # hello_world.py
   print("Hello, World!")

3. Save the File: Save the file with a .py.py extension, such as hello_world.pyhello_world.py.

4. Run Your Python Script: Follow the steps mentioned above to navigate to the file’s directory in the command line or terminal and run the script.

Important Python Commands

Interactive Mode

Python comes with an interactive mode that allows you to execute Python commands line by line.

• Open Interactive Mode:

C:\Users\Your Name>python
Python 3.11.2 (tags/v3.11.2:878ead1, Feb  7 2023, 16:38:35) [MSC v.1934 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> print("Hello, World!")
Hello, World!

C:\Users\Your Name>python
Python 3.11.2 (tags/v3.11.2:878ead1, Feb  7 2023, 16:38:35) [MSC v.1934 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> print("Hello, World!")
Hello, World!

• Exit Interactive Mode:

C:\Users\Your Name>python
Python 3.11.2 (tags/v3.11.2:878ead1, Feb  7 2023, 16:38:35) [MSC v.1934 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> print("Hello, World!")
Hello, World!
>>> exit()
C:\Users\Your Name>

C:\Users\Your Name>python
Python 3.11.2 (tags/v3.11.2:878ead1, Feb  7 2023, 16:38:35) [MSC v.1934 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> print("Hello, World!")
Hello, World!
>>> exit()
C:\Users\Your Name>

Running a Python File

• Run a Python Script:
  command

  python your_script.py

  command

  python your_script.py

Virtual Environment

Virtual environments help manage dependencies for different projects.

• Create a Virtual Environment:

  command

  python -m venv venv

  command

  python -m venv venv

• Activate Virtual Environment:

  • Windows:
    command

    .\venv\Scripts\activate

    command

    .\venv\Scripts\activate

  • macOS/Linux:
    command

    source venv/bin/activate

    command

    source venv/bin/activate

• Deactivate Virtual Environment:

  command

  deactivate

  command

  deactivate

Package Management (pip)

pip is the package installer for Python.

• Install a Package:

  command

  pip install package_name

  command

  pip install package_name

• Install from Requirements File:

  command

  pip install -r requirements.txt

  command

  pip install -r requirements.txt

This should give you a solid start on running Python code, creating files, and using some essential commands. Explore more with our tutorials on Python Central Hub!